Dana 60 docdiff axles

You have the newer style of green bearings with the loose ring. The snap ring keeps the bearing in the housing bore.
There should be a "O" ring to seal the bearing to the bore. I usually put a thin smear of silicone
on the "O" ring just because.
The factory used a closed cell white foam gasket and a paper gasket also but no "O" ring.
I have seen steel shim gaskets also.
With the siliconed "O" ring the orientation likely doesn't make much difference as the seal has been made.
If my memory is correct the steel shim went behind the backing plate and the foam was behind the bearing flange. Aftermarket bearings used the paper behind the bearing flange.